Thunderbird Community Forum

When I open Thunderbird (Mozilla), my files are not current. In other words, the most recent emails, probably since the last time I used Thunderbird, in my file folders are missing. I have tried changing the server settings but I think they are correct. Please be patient with me, I am unfamiliar with all the terminology, etc. Also, when I first enter Thunderbird, it does not recognize my password. A window opens with the message "Login to server imap.postoffice.net with username john.fn@usa.net failed." That message also appears when I click on Get Messages. Thanks for any help.

I have used Thunderbird for years without issue. In the last 2 days, it keeps crashing on one of my laptops (fine on the other). I sent a crash report, but I can't reopen Thunderbird. I tried both quitting and restarting. I shut down my computer and restarted it. I tried updating by downloading the latest version, but that didn't work either. I completely uninstalled it, reinstalled it, and it worked for a few hours. Now, it is back to the Crash Report.

Any suggestions? I love TB and don't want to switch to something else.

Christine

Thunderbird is not synchronizing with Mailfence. My other email accounts (Outlook, Gmail) work fine. TB connects to them, downloads message headers and displays the number of messages correctly. With Mailfence, the messages stop at "connected to imap.mailfence.com" and stalls there. The message disappears after a few seconds and nothing else happens. This happened this morning when I first launched TB. I then got an update to 128.11.1. No change. I did receive the Windows Update 2025-06 Cumulative Update sometime overnight prior to launching TB.

Am getting this message along with a recurring download of a specific email (keeps coming back even after deletion) that does not allow any other new messages to be downloaded. I do see new emails on my phone but will not read into Thunderbird??

Error: "Unable to write the email to the mailbox. Make sure the file system allows you write privileges, and you have enough disk space to copy the mailbox."

Tried: Troubleshooting, closing Thunberbird and reopening, rebooting windows system, compacting, etc. to no avail....

I was using Thunderbird for Windows 10 normally for many months. Recently, whenever I launch the app it immediately freezes, and I have to force quit the application. Reinstalling the app does not fix the issue. I haven't tried deleting my profiles yet, but I would like to avoid that if possible.

Guten Tag, ich arbeite mit Thunderbird auf Linux Mint. Jeweils in den aktuellsten Versionen: Linux Mint 22.1 Cinnamon Thunderbird 128.11.0esr (64-Bit)

Auf meinem bisherigen Rechner begann Thunderbird mit dem letzten Upgrade von Linux Mint langsamer zu laufen. Da ich mir nicht anders zu helfen wusste, habe ich in einen neuen Computer investiert. Obwohl der Rechner jetzt deutlich performanter sein sollte, hängt Thunderbird mindestens genauso wie vorher. Zum Teil ruft Thunderbird auf dem neuen Rechner auch keine neuen E-Mails mehr ab. Ein Neustart korrigiert das zwar wieder, aber beim nächsten Start kann es dann wieder genauso sein.

Alles, was man in den Foren findet, um Thunderbird schneller zu machen, habe ich erledigt. Cache gelöscht, im abgesicherten Modus gestartet (da ist Thunderbird genauso langsam). Auch verschieben von Nachrichten in Archivordner brachte keine wirkliche Besserung.

Ich nutze Thunderbird für 7 Kalender (zum Teil lokal) und 10 E-Mail-Adressen bei unterschiedlichen Anbietern.

Als Add-on habe ich DKIM Verifyer installiert und aktiv.

Ehrlich gesagt, bin ich inzwischen ziemlich verzweifelt, was das Thema angeht. Witzigerweise lassen sich die Entwicklerwerkzeuge nicht aufrufen. Keine Ahnung, ob das vielleicht ein Indiz für den Fehler sein könnte.

Hat jemand eine Idee? Oder noch Fragen?

Herzlichen Dank.

Running Win10, all the sudden I'm getting Not Responding messages, failures to connect to server, and slow deleting of emails. I tried everything: uninstalling/reinstalling; running on troubleshooting mode; checking compatibility. Nothing works. Any ideas?

Thank you

I believe with Update 154,0 my thunderbird has been freezing up. I can't see, to compress files or select some folders. After a few minutes everything freezes up. 21 AUGUST 2026

[redacted] @gmail.com

/edit: unlocked as other was made as duplicate.

Ich erhalte die Meldung "Nachrichten konnten nicht in die Mailbox-Datei geschrieben werden. Stellen Sie sicher, dass das Dateisystem Ihnen Schreibrechte einräumt und genügend Speicherplatz zur Verfügung steht, um die Mailbox zu kopieren." Speicherplatz ist genügend vorhanden. Bis jetzt konnte ich meine Emails problemlos abholen. Bin erreichbar über Telefon [edited] oder Handy [edited phone#'s from community support forum]

Need help with Thunderbird. No matter what I tried always comes back to the same problem.

Problem: Keep getting message non responding. Very buggy, difficult deleting emails (will delete after a prolong period of time > 5 sec). When typing a message there will be no characters then after a short period of time the charterer typed shows up. Sometime without and reason while using Thunderbird it close by itself.

What I have down to solve the problem: 1. Start in safe mode Thunderbird operates as expected with any issues. 2. Win 10 environment, closed all apps and made sure there was no extensions running. Made sure the only app open on the task manger was Thunderbird. NO SOLUTION FOUND 3. Download and install latest version of Thunderbird. NO SOLUTION FOUND 4. Created a new profile file. NO SOLUTION FOUND

Need help, what else is there to try short of a total Nuclear solution?

I opened Thunderbird and could not get to the inbox or any other folders—it shows only the donations page. This is not okay. I do donate. Not much, not too often, but I do. However, if I open e-mail client and want to use it, then this is not a right moment to asking for donations. Or I should be able to do what I came to do and deal with donations issue later.

If you want users to pay for Thunderbird, it is of course okay, but please let us know in advance, give some time to mull it over and then clear the sheets. It is most inconvenient when this kind of issue is raised when you actually need to do something. And the message is unclear - how often and how much I need to donate (pay) in order to get to use Thunderbird without interruptions?

Thank you in advance and I do like Thunderbird. Just not this approach.

PS. Sorry for my bad English, not native speaker. PPS. Or, maybe this is some error that donations page does not "go away"?

Thunderbird stopped working and crashes at startup. It fails also in safemode. Any idea?

Detailed information below:

AdapterDeviceID: 0x4690 AdapterDriverVendor: mesa/iris AdapterDriverVersion: 23.2.1.0 AdapterVendorID: 0x8086 Add-ons: default-theme%40mozilla.org:1.3 AvailablePageFile: 0 AvailablePhysicalMemory: 3816996864 AvailableSwapMemory: 2044719104 AvailableVirtualMemory: 24182190080 BackgroundTaskMode: 0 BuildID: 20240417192958 ContentSandboxCapabilities: 119 ContentSandboxCapable: 1 ContentSandboxLevel: 0 CrashTime: 1729614811 DOMFissionEnabled: 1 DOMIPCEnabled: 1 DesktopEnvironment: ubuntu:gnome EMCheckCompatibility: true GpuSandboxLevel: 0 GraphicsNumActiveRenderers: 1 GraphicsNumRenderers: 1 HeadlessMode: 0 InstallTime: 1714494098 IsWayland: 1 LastStartupWasCrash: 1 Notes: Ubuntu 22.04.4 LTSFP(D00-L1000-W0000000-T010) WR? WR+ EGL? EGL- GL Context? GL Context+ ProductID: {3550f703-e582-4d05-9a08-453d09bdfdc6} ProductName: Thunderbird ReleaseChannel: release SafeMode: 0 SecondsSinceLastCrash: 162 StartupCacheValid: 0 StartupCrash: 0 StartupTime: 1729614649 SubmittedFrom: Client TelemetryEnvironment: {"build":{"applicationId":"{3550f703-e582-4d05-9a08-453d09bdfdc6}","applicationName":"Thunderbird","architecture":"x86-64","buildId":"20240417192958","version":"115.10.1","vendor":null,"displayVersion":"115.10.1","platformVersion":"115.10.0","xpcomAbi":"x86_64-gcc3","updaterAvailable":false},"partner":{"distributionId":null,"distributionVersion":null,"partnerId":null,"distributor":null,"distributorChannel":null,"partnerNames":[]},"system":{"memoryMB":31760,"virtualMaxMB":null,"cpu":{"extensions":["hasMMX","hasSSE","hasSSE2","hasSSE3","hasSSSE3","hasSSE4_1","hasSSE4_2","hasAVX","hasAVX2","hasAES"]},"os":{"name":"Linux","version":"6.5.0-28-generic","locale":"fr-FR","distro":"Ubuntu","distroVersion":"22.04"},"hdd":{"profile":{"model":null,"revision":null,"type":null},"binary":{"model":null,"revision":null,"type":null},"system":{"model":null,"revision":null,"type":null}},"gfx":{"D2DEnabled":null,"DWriteEnabled":null,"ContentBackend":"Skia","Headless":false,"EmbeddedInFirefoxReality":null,"adapters":[{"description":"Mesa Intel(R) UHD Graphics 770 (ADL-S GT1)","vendorID":"0x8086","deviceID":"0x4690","subsysID":null,"RAM":0,"driver":null,"driverVendor":"mesa/iris","driverVersion":"23.2.1.0","driverDate":null,"GPUActive":true}],"monitors":[{"screenWidth":1920,"screenHeight":1200}],"features":{"compositor":"webrender","hwCompositing":{"status":"available"},"gpuProcess":{"status":"unused"},"webrender":{"status":"available"},"wrCompositor":{"status":"blocked:FEATURE_FAILURE_DISABLE_RELEASE_OR_BETA"},"openglCompositing":{"status":"available"},"omtp":{"status":"unused"}}},"appleModelId":null,"hasWinPackageId":null},"settings":{"blocklistEnabled":true,"e10sEnabled":true,"e10sMultiProcesses":8,"fissionEnabled":true,"telemetryEnabled":false,"locale":"en-US","intl":{"requestedLocales":["fr-FR"],"availableLocales":["en-US"],"appLocales":["en-US"],"systemLocales":["fr-FR"],"regionalPrefsLocales":["fr-FR"],"acceptLanguages":["en-US","en"]},"update":{"channel":"release","enabled":true,"autoDownload":false,"background":false},"userPrefs":{"browser.fixup.alternate.enabled":false,"browser.search.region":"FR","network.trr.strict_native_fallback":false,"security.tls.version.enable-deprecated":true,"widget.content.gtk-high-contrast.enabled":true},"sandbox":{"effectiveContentProcessLevel":0,"contentWin32kLockdownState":3},"addonCompatibilityCheckEnabled":true,"isDefaultBrowser":null},"profile":{"creationDate":19727,"firstUseDate":19727},"addons":{"activeAddons":{},"theme":{},"activeGMPlugins":{"dummy-gmp":{"version":"0.1","userDisabled":false,"applyBackgroundUpdates":1}}}} Throttleable: 1 TotalPageFile: 35349712896 TotalPhysicalMemory: 33302896640 UptimeTS: 161.82273505 Version: 115.10.1 useragent_locale: en-US

This report also contains technical information about the state of the application when it crashed.

Hi everyone,

Long time, happy TB user and supporter. A new problem has appeared with nebula that I am hoping that the experts here can help me troubleshoot.

When any operation is performed on the emails in one particular account's Inbox folder, there is a 3-5 second pause where TB freezes. For example, when I try to open an email, I see a blank email tab with `Loading Message...` for a few seconds, before the email shows; when I toggle the read status for an email in the folder by clicking on the gray/green icon, there is a few seconds' delay. During this pause I can hear my CPU fan speed up, so seems like there is a spike in CPU usage. After a few minutes, these delays go away, but then reappear at some point (even though TB has been open the entire time) - possibly after new email has been downloaded from the server.

My overall suspicion is that something in this particular folder's files is triggering Nebula. I need help figuring out what it is and fixing it. This is not bad enough for me to ditch TB but it's definitely annoying AF. Strange part is that it appeared only after the Nebula upgrade, which makes me think this is a code issue not a mailbox file issue.

Setup

1. Thunderbird 128.3.3esr (64-bit) on Windows 11 23H2
2. Multiple mailbox accounts, all using POP3 (not IMAP; there is no interaction between TB and the server other than downloading email). Had not changed any settings during the nebula upgrade
3. The account in question has multiple folders in TB. Filters are used to move messages from the Inbox to different folders (and sometimes, to folders on other accounts). Again, the slow performance is only on the single, Inbox folder in one account, and not any of the other folders or other accounts.
4. Profile files are on a very fast SSD. I have not been able to detect a peak in disk usage when the pause happens.
5. The affected folder has 32K emails in it, size on disk 1.5G (+27M for `.msf` file). I have another folder which is 3.1G+20M, that one does not have this problem.

Here's what I have tried, with no changes

1. Compact all mailboxes
2. Repair folder for all folders/subfolders
3. Delete the GLODA to force a rebuild
4. Troubleshooting mode
5. Watching the console in developer tools (no relevant errors appear)
6. Turning on `browser.dom.window.dump.enabled` - no significant errors appear
7. Turning off hardware acceleration
8. Updating graphics card drivers
9. Ensuring that the TB profile folder and windows temp folder is not being indexed by Windows search
10. Checking the filter logs - no errors

Any suggestions or tips on how to gather more data, are welcome. Thanks!

Thunderbird Quick Filter Toolbar has suddenly started splashing a couple popups when I start typing in the filter box. These popups effectively say "... click to..." but don't actually let me click; they just block the screen.

For >20 years I have used Thunderbird as my email reader for various email accounts on my mac laptop. Last night Thunderbird stopped downloading emails from my yale.edu account. I tried removing the yale account and reinstalling it unsuccessfully. See attachment. The Yale IT rep told me that Yale very recently added security features that are probably preventing Thunderbird from working with it. They told me to use the Outlook app. Is there anyway I can get Thunderbird to work with my yale.edu outlook email account?